In this March 3, 2015 photo, a group of California sea lions rest on a large bouy in the San Ignacio lagoon, in the Pacific Ocean, near Guerrero Negro, in Mexico's Baja California peninsula. (Photo by Dario Lopez-Mills/AP Photo)

In this March 12, 2015 photo, a man tours a graffiti exhibition at the Museum of Modern Art, in Bogota, Colombia. The city-run museum recently held an exhibition highlighting the work of Bogota street artists who go by aliases such as Joems and the MonsTruacioN collective. (Photo by Fernando Vergara/AP Photo)

“Catch of the Decade”. Can you guess what happened next? Photo location: Katmai National Park, Alaska, USA. (Photo and caption by Aaron Baggenstos/National Geographic Photo Contest)

A visitor looks at a sculpture by a Chinese artist Chen Wenling at the "Sculpture by the Sea" exhibition which runs along the Bondi to Tamarama coastal walk in Sydney on October 22, 2015. The world's largest annual free-to-the-public outdoor sculpture exhibition runs from October 22 – November 8 this year and features over 107 sculptures by artists around the world. (Photo by Saeed Khan/AFP Photo)

Local residents crowd a swimming pool during a hot weather in Suining, Sichuan province, 27 July 2008. (Photo by Reuters/Stringer)

The rarely seen blue sharks photographed by Saeed Rashid in British waters. Elusive blue sharks have recently been spotted off the south coast of England, having moved to the UKs warmer waters to hunt. The carnivorous sharks have been lurking off the coast of the popular British holiday destination, Penzance, in Cornwall. (Photo by Saeed Rashid/Caters News)

Open jaws of a Great White Shark Carcharodon Carcharias, South Africa. (Photo by Stephen Frink Collection/Alamy Stock Photo)

A photographer in Somerset, South West England captured the mating rituals of toads as several males attempt to mate with one female all at once. (Photo by John Waters/NPL)